A:4
B:-4
C:8
D:-8
在1991,1992,1993,1994,1995,1996,1997,1998这八个数中,不能写成两个自然数的平方差的数是 ____ .
⑴ ____ A. I like Chinese.
⑵ ____ B. The turtle has four legs.
⑶ ____ C. The birthday cake is beautiful.
⑷ ____ D. This is my basketball.
⑸ ____ E. Touch your nose.